When and how did female breasts become sexualized?

by KelbyLK

I live in the USA so if that specificity makes it easier to answer by all means :) curious when and how female breasts became sexualized, "indecent" to expose in public, etc. #freethenipple

cromulent_weasel

This is a question that predates recorded history so perhaps /r/AskAnthropology would be a better place?